Simultaneous Determination of the Time and Space Correlations of Density Fluctuation in Glass Transition of Supercooled Liquid

同时测定过冷液体玻璃化转变中密度涨落的时间和空间相关性

• 批准号: 12640365
• 负责人: TSUJIMI Yuhji
• 金额: $ 2.37万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640365/
• 关键词: glass transition; density fluctuation; structural relaxation; space-time correlation; scaling; impulsive stimulated thermal scattering; D-ソルビトール

The purpose of this study is to investigate the possibility of the time-space sealing law associated with glass transition of supercooled liquid. The impulsive stimulated thermal scattering (ISTS : one of time-domain measurements) has been performed for this purpose. ISTS can determine not only the time correlation of the density fluctuation directly but also the space correlation of the density fluctuation at the same time by changing the scattering wave vector q (changing the observation length scale Λ = 2π/q).The density fluctuation has been observed in three typical glass forming liquids ; D-sorbitol, glycerol, and salol. The q dependence of the density fluctuation has been successfully measured and the new phenomenon has been found commonly in these materials. The relaxation time τ_R of the density fluctuation shows an anomalous peak at the particular temperature T_<max> (much higher than the glass transition temperature T_g). Moreover, we firstly found that T_<max> approaches T_g with decreasing in q. This phenomenon implies the existence of the length scale ξ characterizing the space correlation of the density fluctuation. Since it is natural to think that ξ is growing with decreasing in temperature, we think that T_<max> is the temperature where ξ = Λ.

本研究的目的是探讨与过冷液体玻璃化转变相关的时空封闭规律的可能性。脉冲受激热散射（ISTS：时域测量之一）已被用于这一目的。通过改变散射波矢q（改变观测尺度Λ = 2π/q），ISTS不仅可以直接测定密度涨落的时间相关性，而且可以同时测定密度涨落的空间相关性，并在D-山梨醇、甘油和Salol三种典型的玻璃形成液体中观测到了密度涨落。成功地测量了密度涨落的q依赖性，发现了这些材料中普遍存在的新现象。密度涨落的弛豫时间τ R在特定温度T_<max>（远高于玻璃化转变温度T_g）处出现反常峰。此外，我们还首次发现，<max>随着q的减小，T_g逐渐接近T_g。这一现象暗示了描述密度涨落空间相关性的长度尺度的存在。由于我们很自然地认为温度随温度的降低而增加，所以我们认为T_<max>是温度，其中温度= Λ。

项目成果

M. Kobayashi: "Relaxation Dynamics in Glycerol Studied by Im pulsine Stimulated Thermal Scattering"Journal of Non-crystalline solids. (in press). (2002)

M. Kobayashi：“通过脉冲刺激热散射研究甘油的松弛动力学”非晶固体杂志。

M.Kobayashi: "Relaxation Dynamics in Glycerol Studied by Impulsive Stimulated Thermal Scattering"Journal of Non-crystalline Solids. (in press). (2002)

M.Kobayashi：“通过脉冲受激热散射研究甘油的弛豫动力学”非晶固体杂志。

M. Kobayashi: "Relaxation Dynamics in Glycerol Studied by Impulsive Stimulated Thermal Scattering"Journal of non-crystalline solids. (in Press). (2002)

M. Kobayashi：“通过脉冲受激热散射研究甘油的松弛动力学”非晶固体杂志。